| Micro-electromechanical-systems (MEMS) are of the characteristic such as small size, light weight and compact integration. Friction, wear and stiction are the important factors affecting the performance and reliability of MEMS. Surface modification of the microstructure materials has been an effective means of improving friction, reducing wear, restraining stiction and enhancing stability of MEMS. Molecular thin films technique is one of the effective ways to improve friction and reduce wear in order to enhance the stability and reliability of MEMS.Self-assembly technique is an effective technique developed in the recent 30 years preparing super thin film. The researchers are interested in the excellent lubricant performance of self-assembled monolayers (SAMs) and pay a lot of attention to the preparation and tribological behavior of self-assembled monolayers.In this paper, self-sssemble technique has been used to prepare thin films in view of the defects of currently used surface modification methods in MEMS. The mechanical and tribological properties have been improved due to the special physical chemical characteristics of rare earths. Some significant original results have been obtained.Firstly, silane/rare earth composite films were prepared by self-sssemble technique on the substrate of silane SAMs. The films'surface morphology of the films was analyzed by atomic force microscopy (AFM); the chemical composition and phase transformation of the films'typical elements was analyzed by X-ray photoelectron spectroscopy (XPS); the films'surface energy was evaluated by contact angle measuring equipment. The process and mechanism of the self-assembly was researched by the experimental results.Secondly, the variation value of the rare earth free energy is -336 KJ/mol in self-assembly processes by thermofynamic calculation, which indicated that the RE can... |
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